All of the men were placed in custody after the scandal broke at the start of the year embroiling Satyam, a celebrated symbol of India's global outsourcing prowess.

In April, mid-sized Indian computer outsourcer Tech Mahindra, part of leading Indian vehicle maker Mahindra and Mahindra, paid nearly 600 million dollars for a majority share in the company, rescuing it from collapse.

Satyam was ranked as India's fourth-largest outsourcer by revenues when the scandal broke and its clients included some of the world's biggest companies such as Nestle, General Electric and General Motors.

Satyam Computer Services, based in the southern Indian city of Hyderabad, re-branded itself in June as Mahindra Satyam in a bid to recover from the country's worst-ever corporate accounting fraud.

The Satyam founder underwent emergency treatment at a Hyderabad hospital in September after suffering a suspected heart attack, medical officials said.

He is still in hospital being treated for cardiac problems and for hepatitis, officials say.

The fraud office will launch proceedings on about 30 charges, mostly under the Companies Act of 1956, the Press Trust of India reported at the weekend.

The Central Bureau of Investigation will pursue about half a dozen charges involving criminal offences under the penal code.

The Serious Fraud Investigation Office is an arm of the Corporate Affairs Ministry.

Its move to prosecute comes after it submitted reports to the government detailing alleged violations of company law.

Kurshid said earlier this month his ministry had devised a system under which the government would be able to detect corporate fraud at an early stage.

Officials would check periodically on revenues and profits. The system would highlight any abnormality in record-keeping, he said.

Investment house Goldman Sachs has cited "governance" -- both corporate and political -- as the biggest challenge facing India in attaining its economic potential.